The U.N. nuclear agency has cut back almost half its aid projects in Iran to uphold U.N. sanctions imposed on Tehran over its disputed nuclear energy program, according to a report obtained by Reuters on Friday.　　

Details of the cutback emerged shortly after Iran's chief nuclear negotiator canceled a trip to a conference in Germany, where United Nations officials had hoped talks with European policymakers would win a breathing space in the nuclear row.

The aid reduction, based on a review by International Atomic Energy Agency experts, will go for final approval to a March meeting of the IAEA's board of governors.

"This is a substantial cut in the technical aid program for Iran," said a senior U.N. official familiar with it. "It is a message of inducement to Iran to reconsider its course."

Iran was hit with sanctions over its failure to prove to the IAEA that experimental efforts to enrich uranium are geared solely to generating electricity as it maintains.

Of 55 IAEA technical aid projects in Iran, 10 were halted entirely and 12 partially blocked as they could violate the December 23 Security Council sanctions resolution against Tehran.

"No technical cooperation may be provided to Iran that relates to the proliferation of sensitive nuclear activities specified in the resolution," namely enrichment of uranium, fuel reprocessing or heavy water production, the IAEA review said.

Projects stopped as a result of the U.N. watchdog's confidential reassessment, issued in the name of IAEA director Mohamed ElBaradei, related mainly to strategic nuclear power planning and generation of nuclear fuel.

IAEA projects in Iran have supported work on radio-pharmaceuticals and isotopes for medical care and agriculture, radioactive waste management, nuclear power planning and safety regulations, and training courses.

The cancellation of the trip to Germany by Iran's Ali Larijani dashed hopes for a quick return to diplomacy in the deepening row between Tehran and the West.

"We have heard that Mr. Larijani will not be coming to the conference due to illness," said Horst Teltschik, chief organizer of the Munich Security Conference.

Earlier, ElBaradei urged the two sides to avoid "an uncontrolled chain reaction" toward conflict and said he hoped a solution would be found at the Munich talks.